It is known that in many regulation system, the detection of a magnitude used as a parameter for the regulation must be so carried out as to keep into account the different sensitivity the magnitude concerned has as a function of its instantaneous value in the process which is being monitored. Stated another way, it is required that the magnitude concerned be detected with a different resolution degree as a function of the value such magnitude takes within the range of its variability.
This is the case, for example, with the operative parameters of an internal combustion engine, such as speed of rotation, angle of the throttling butterfly and others, which are generally employed as regulation parameters for governing the working conditions of such engine, such as carburation, ignition advance and others.
For example, in the regulation processes in which a higher regulation accuracy is required at low RPMs than at high RPMs of an engine, it is imperative that the speed signal delivered by the transducer displays a considerable number of digital values in correspondence with the low RPMs, whereas, at higher RPMs a lower number of digital values is requested.